61 Aquarii, abbreviated 61 Aqr, is an orange-hued star in the zodiac constellation of Aquarius. 61 Aquarii is its Flamsteed designation. It has an apparent visual magnitude of 6.39,[2] which indicates it is a dim star that requires good seeing conditions to view. Based upon an annual parallax shift of 6.53 mas[1] as seen from Earth's orbit, the star is located around 500 light years away. It is moving closer to the Earth with a heliocentric radial velocity of −8 km/s.[4]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquarius |
| Right ascension | 22h 35m 48.80173s[1] |
| Declination | −17° 27′ 37.5415″[1] |
| Apparent magnitude (V) | 6.39[2] |
| Characteristics | |
| Spectral type | K4 III[3] |
| B−V color index | 1.420±0.015[2] |
| Astrometry | |
| Radial velocity (Rv) | −8.1±2.9[4] km/s |
| Proper motion (μ) | RA: −29.242[1] mas/yr Dec.: −41.566[1] mas/yr |
| Parallax (π) | 6.5274 ± 0.0513 mas[1] |
| Distance | 500 ± 4 ly (153 ± 1 pc) |
| Absolute magnitude (MV) | 0.53[2] |
| Details[5] | |
| Mass | 0.572±0.031 M☉ |
| Radius | 11.754+0.611 −1.450 R☉ |
| Luminosity | 126.56[2] L☉ |
| Surface gravity (log g) | 2.401+0.180 −0.045 cgs |
| Temperature | 4430+141 −53 K |
| Metallicity [Fe/H] | 0.099+0.120 −0.100 dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an evolved K-type giant star with a stellar classification of K4 III,[3] which indicates it has consumed the hydrogen at its core and expanded. It has an estimated 0.57 times the mass of the Sun but with over 11 times the Sun's radius. The star is radiating 127 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,430 K.[5]
References
edit- ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051.
- ^ a b c d e Anderson, E.; Francis, Ch. (2012), "XHIP: An extended Hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
- ^ a b Houk, Nancy; Smith-Moore, M. (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 4, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1988mcts.book.....H.
- ^ a b Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system", Astronomy Letters, 32 (11): 759–771, arXiv:1606.08053, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065, S2CID 119231169.
- ^ a b Huber, Daniel; et al. (2016), "The K2 Ecliptic Plane Input Catalog (EPIC) and Stellar Classifications of 138,600 Targets in Campaigns 1-8", The Astrophysical Journal Supplement Series, 224 (1): 2, arXiv:1512.02643, Bibcode:2016ApJS..224....2H, doi:10.3847/0067-0049/224/1/2, S2CID 118621218.
- ^ "61 Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved October 24, 2018.